Apple Security Update 10.9.2: Please Update

Apple has recently released an update to address an important security issue in OS X 10.9 Mavericks. Please backup your computer and update to 10.9.2.

To perform this update:

Click on the Apple logo in the top left corner

Select “Software Update”

This will open up the App Store, where you can see what updates are available for your computer and install them by clicking the gray button labeled “Update”. For more detailed instructions, please see this Apple Support Article.

The vulnerability is an apparently errant line in Apple’s “Secure Transport” API that causes signature verification to never fail. This allows unchecked attackers to impersonate “trusted” servers and intercept and decrypt communications at will. So it is important that you update as soon as possible.